Users often do not like complex value searches and instead prefer the ease of use of a DDLB. DDLBs are one of the most commonly used controls for data selection. They are easy to use and well received by end users. DDLBs typically allow a user to select a single value. However, depending on the amount and structure of possible entries, different selection modes may be necessary to best meet the user's requirements. Examples of common selection modes are hierarchical value structures or tree structures. These selection modes may be used, for example, to display positions in an organizational structure, skills in a skills catalog, or products in a product catalog. Currently, these selection modes require the user to switch screens to access them. Alternatively, they may appear in a modal pop-up window. In either case, the user's task flow is interrupted.
DDLBs are limited in function. For enhanced searching, more cumbersome mechanisms must be employed. DDLBs contain a single column and therefore only allow for simple value searches. A user may type a character and the value list may then position the cursor at the first hit of the character in the list. Each time the character is pressed on the keyboard, the cursor may be moved to the next choice in the DDLB which begins with that character. In contrast, extended value searches usually appear in a modal pop-up with a two column (key/value) table and a filter row. The user selects a table entry in a certain row and thereby applies the selected entry to the input field. Once again, the modal pop-up window interrupts the user's work flow.